Tonnage calculator



. g p 8 e) 3 5 FT 2 VH2 HD 22 I- ARD 23 0, l2 l3 5 m (P15 02 g1: 47 t 5! 37 April 34, 1951 R. J. DRESHER I 2,550,458

TONNAGE CALCULATOR Filed Dec. 14, 1949 3 Sheets-Sheet 1 INVENTOR ROBERT J. DRESHER HIS ATTORNEYS April 24, 195% R. J. DRESHER TONNAGE CALCULATOR 3 Sheis-Sheet 2 Filed Dec. 14, 1949 INVENTOR ROBERT J. DRESHER HIS ATTORNEYS April 24, 1951 R. J. DRESHER TONNAGE CALCULATOR 3 Sheets-Sheet 3 Filed Dec. 1 1949 INVENTOR ROBERT J. DRESHER HIS ATTORNEYS Patented Apr. 24, 1951 UNITED TQNNAG'EiICALCULATOR Robert J.,', Dresher, Dayton, .Ohio Application rDecember l l, 1949, Serial 'No. 1325850 4cClaimsh (01. 2353-88) This invention relates 5130;, improvements. in. tone nagepalculators and, pa-rticularly to ,a means for, quickly. calculating; the iorce required rto punchr a blank; from sheet pmetal ior. calculating the forcegrequired ,forstripping ,the punched .blank 5 fromzethe die, and for, determining, the; size .offt the die requiredv to withstand the. pressure In designing. punch and die, sets, theforcesfori punching and stripping blanksin va punch and.

die set .require time-consuming calculations, be-,

causegtheforces required aredependent'on the sizecof the blank to be punched; its thickness," andthe kind of material'used.

Another problem is to determine whether or 5 not. a given punch press has sufficient powerpto punch? out the parts, so thatitcan be predeterr' mined which punch" press can be used and thediesetidesigned-for mounting on the'selected punch press.

The'principal' object of the inventi'onis-toprovide a icalculator for determiningall factors I requiredjfor designing-a-punch-and die' set 'forsx a" given blank -to -be punched:

It is a specific object of---the invention to-pro-- vide ar simple -ca1culator-for determining the tonnage required for punching -outa blank and: for stripping the blankfrom the-=-punch -of,.apunchand die-set,- and thearea-required-for thebase of a punch .of the punch anddie set: to support the load placed thereon during a punching operation.

Another specific object of the invention-ist0= provide a calculator having certain factorscem bodied therein, which factors can be-determined-l by setti-nga movable element relatively-to acome I mon scale;

With these and incidental objects inview, 'the. invention includes certain novelfeatures of -con -x... struction and combinationsof parts a preferred form-of which is hereinafter described with ref.-. e40,

erence to the drawings :which accompany: and form apart of this specifications of said drawings r Fig; 1 is an elevationaliview.showingonesfacec of the calculator.

General description Before a punch? andidie set can .be properly designed :to. fit a selected .punchr'apr-essg..thertons name required to. punch out ablankl f romza ,given; material must be determined; so :thatsthes. puncha and; 2 die; set can; be... designedz toz fit-tthea punch:

2-. press; or:vic,e ,versa, so'that it can be determinedf; if; a.-;givenpunch press has Vsufficient tonnage ca,- pacity 1 to do. thezwork required:

Itj'zis; also necessarytodetermine the pounds-g. pressurerequiredutostrip the blank fromithei; punch,;.so:: that springs-7'; of the? proper str.engt lirv usually employedrforthis purpose can be -supplied:

Another factor to be determinedds ,the,mini;- mum ;;squar e,area required forpthe base of; the punch; so; that, the:- punch can ,1 withst nd; the; load :placed thereon when: the punching; 013811211 tionis-performed.

Theabove factors arelgoverned by. the lengths of .;the:-:cutt ing edges of;-,;the part; to ,be blanked; andzthewkind and. thickness of ;the material;

Thegfirst step-in; the calculations :is to measev. ure the total-length of theccutting edges of the part tobeblanked; If the ,part is a solid piece/1.. containing rno openings or; holes, the length; Of}; the-perimeteris'first measured.-,, IfAopehingS are: tosbe simultaneously punched in the; Piece-the 1 perimeter vof :the, opening; or openings is meas;- uredand; the, total thereof. calculated.v The: present: :scaleyhas these :lengths: calibrated in; inches and graduated on the outer edge of the calculator dial. A disk "having Windows therein, togexpose factors corresponding to. various materials, is rotated on the calculator-disk .une til' apointer thereon coincides with the total. length calculated. The factorintons necessary, to punch the blank is then read from theselectedj window. Thus, the. firstiactor is obtained.

To .obtain the pounds pressurenecessary to strip the blank. from .thepunch, the above-mentionedc pointer coincides with the saidscale on; theicalc'ulator dial, and this time the scale repre: sentstons instead ofinches. Aiter'the said; pointer has been set. into thesecond position.rel= atively to the scale-the pounds pressure required 1, is ;r e,a,d..from,.th scale marked stripping scale on. Fig. 1 of the drawings. It may be noted at this; point that .the stripping scale? shown 5, herein is calibratedto 5% of the tonnage required j. for punching, asthis has been found satisfactory fortsmall parts.

The next factor-that is, the area required to safelysupport the punch-is read from a scale .4 marked area scale on thedrawings.v This face toris read through a windowin the rotatable disk while the pointer thereonis in, the tonnage, selecting. position.

Detailed description and the disk ll, together with a second disk 20, can be rotated. The dial l and the disks H and 20 are positioned on the arbor H, where a head [8 of the latter and a washer l9 staked to the arbor maintain the calculator in assembled position. The arbor I1 is of a size to permit easy rotation of the parts thereon.

The window [2 is located in the disk II in a position wherein sections of the scales 2|, 22, and

23 can be exposed to view upon rotation of the dial l0. Similarly, sections of scales 24, 25, and 26 can be exposed to view through window l3; sections of scales 2?, 28, and 29 can be exposed through window [4; sections of scales 30, 3!, and 32 can be exposed through window and sections of scales 33, 34, and 35 can be exposed through window i6. Sections of a scale 36 can be exposed through a window 37, and sections of a scale 38 can be exposed through a notch or window 39 on the perimeter of the disk ll. Also, lying outside the perimeter of the disk H, is a scale 40, which is always exposed to view in its entirety. The scale 40 serves a dual purpose, explained later.

The scales 2i to 35 inclusive are calibrated toindicate the tons pressure required for materials of various thickness and condition. For example, scale 2! is calibrated to indicate tonnage factors for soft material, .062 inch thick; the scale 22 is calibrated to indicate tonnage factors for hard material, .062 inch thick. The legends on Fig. 1 indicate the calibration for the various materials for each or the scales shown in Fig. 4. The scales shown in Fig. 3 are calibrated to indicate the tonnage factor for materials .020,

.030, .040, .050, and .060 inch thick and for three degrees of hardness, like that shown in Fig. 4. The disk covers the various scales and is provided with windows similar to those shown in Fig. l to selectively expose sections of these scales.

Operation For the purpose of describing the operation of the invention, the finding of the various factors required for a part having a perimeter of 3'7 inches and made of soft material .062 inch thick will be used.

The first step is to set a pointer 45 (Fig. l) on the disk I l opposite the graduation indicating 3'7 on the scale :30. After this is done, a reading is taken from the scal 2| by observing the graduation at the right-hand edge of window [2. This setting will indicate 30, which factor is calibrated in tons, and therefore it is determined that it will take tons to punch out the blank.

The second step is to set the pointer 45 to indicate 30 on the scale 30. The scale 05 is used first to indicate inches, and for the second step the scale is used to indicate tons. After the pointer has been set to indicate 30 tons on the scal 40, the pounds pressure required to strip the blank from the punch is indicated by a pointer it, which points to the factor 3,000 pounds on the scale 38.

The third required factor is the necesary area of the base of the punch which is required to withstand the pressure applied during the punching operation. This factor is read through the window 37 (Fig. 1) when the pointer 45 is set to 30 on scale 40, and is indicated by the pointer il, which the example assumed points to 10, which is the area in square inches required when based on 3 tons per square inch, the rate found adequate.

While the form of the invention shown and described herein is admirably adapted to fulfill th objects primarily stated, it is to be understood that it is not intended to confine the invention to the one form or embodiment disclosed herein, for it is susceptible of embodiment in various other forms.

What is claimed is:

1. In a device of the class described, the combination of a, base member having a plurality of tonnage scales thereon; a second member mounted on and movable relatively to the base member, said second member having a plurality of windows therein, each window overlying a different one of said tonnage scales; another scale on the base member and located adjacent the perimeter thereof, said another scale indicative of the size of a blank to be punched and being correlated with the plurality of tonnage scales; a pointer on the second member and located adjacent the another scale to guide the setting of the second member into a position in relation to the another scale, said pointer also correlated with the windows in said second member to expose sections of the plurality of scales to view, the windows representing materials of different thickness and degrees of hardness, the plurality of scales being so proportioned and angularly related with the windows as to jointly indicate the tonnage required to punch out a part of given size and character, said pointer on the second member also angularly related to the said another scale so as to indicate the said tonnage requirement; a second pointer on the second member; and a scale on the base member angularly related with the second pointer to indicate the stripping pressure in pounds required to strip the punched part from the punch when the first pointer is set to indicate tonnage on the said another scale.

2. In a device of the class described, the combination of a base member having a plurality of tonnage scales thereon; a second member mounted on and movable relatively to the base member, said second member having a plurality of windows therein, each window overlying a difierent one of said tonnage scales; another scale on the base member and located adjacent the perimeter thereof, said another scale indicative of the size of a blank to be punched and being correlated with the plurality of tonnage scales; a pointer on the second member and located adjacent the another scale to guide the setting of the second member into a position in relation to the another scale, said pointer also correlated with the windows in said second member to expose sections of the plurality of scales to view, the windows representing materials of different thickness and degrees of hardness, the plurality of scales being so proportioned and angularly related with the windows as to jointly indicate the tonnage required to punch out a part of given size and character, said pointer on the second member also angularly related to the said another scale, so as to indicate the said tonnage requirement; a second pointer on the second member; a scale on the base member angularly related with the second pointer to ihdicate the stripping pressure in pounds required to strip the punched part from the punch when the first pointer is set to indicate tonnage on the said second scale; an area scale on the base member; and a Window in the second member. correlated with the first pointer and the area scale to indicate the base area required for a punch capable Of Withstanding the tonnage indicated by the said first pointer. I

3, In a device of the class described, the combination of a, base member having a plurality of tonnage scales thereon; a second member mounted on and movable relatively to the base member, said second member having a plurality of windows therein, each window overlying a plurality of said tonnage scales, which are correlated to indicate tonnage requirements for a specific thickness of material to be punched; another scale on the base member and located on the perimeter thereof, said another scale indicative of the length of the cutting edges of the punch for punching a blank and being correlated with the plurality of tonnage scales; a pointer on the second member located adjacent said another scale to guide the setting of the second member into a position in relation to the said another scale, said pointer also correlated with the said windows to expose sections of the plurality of scales to view to indicate the tonnage required to punch out a part of a given thickness and degree of hardness, said pointer on the second member also angularly related to said another scale so as to indicate the said tonnage requirement; a second pointer on the second member; and a scale on the base member angularly related with the second pointer to indicate the stripping pressure in pounds required to strip the punched part from the punch, when the first pointer is set to indicate tonnage on the said another scale.

4. In a device of the class described, the combi nation of a base consisting of a disk and having a 6 first disk to expose an area of said first disk at the perimeter thereof, said second disk covering the area containing the said plurality of scales; a plurality of Windows in said second disk, each Window registering with one of said plurality of scales to expose sections of said plurality of scales to view; another scale in the said area exposed on the base at the perimeter thereof and calibrated for indicating measurement of length and of tonnage; an indicator on the smaller disk correlated with the tonnage scales so that when the indicator is set to indicate a length on the said another scale the tonnage required to punch a part of the selected dimension is indicated on the tonnage scales, and said pointer thereafter settable on the said another scale to indicate said tonnage; a scale on the base member located between the said another scale and the tonnage scales; and a second indicator correlated with the first indicator and the last-named scale to indicate pounds pressure required for stripping the blank from the punch.

ROBERT J. DRESHER.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 331,264 Tucker Nov. 24, 1885 814,488 Watson Mar. 8, 1906 924,058 Graves June 3, 1909 1,429,463 Squyer Sept. 19, 1922 

